// 该代码来自http://www.ghugo.com/mobile-h5-fluid-layout-for-iphone6/
(function (doc, win) {
	// 分辨率Resolution适配
	var docEl = doc.documentElement,
		resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',
		recalc = function () {
			var clientWidth = docEl.clientWidth;
			if (!clientWidth) return;
			docEl.style.fontSize = 100 * (clientWidth / 320) + 'px';
		};

	// Abort if browser does not support addEventListener
	if (!doc.addEventListener) return;
	win.addEventListener(resizeEvt, recalc, false);
	doc.addEventListener('DOMContentLoaded', recalc, false);

	// 一物理像素在不同屏幕的显示效果不一样。要根据devicePixelRatio来修改meta标签的scale,要注释上面的meta标签
	(function () {
		return;
		var dpr = scale = 1;
		var isIPhone = win.navigator.appVersion.match(/iphone/gi);
		var devicePixelRatio = win.devicePixelRatio;
		if (isIPhone) {
			// iOS下，对于2和3的屏，用2倍的方案，其余的用1倍方案
			if (devicePixelRatio >= 3 && (!dpr || dpr >= 3)) {
				dpr = 3;
			} else if (devicePixelRatio >= 2 && (!dpr || dpr >= 2)) {
				dpr = 2;
			} else {
				dpr = 1;
			}
		} else {
			// 其他设备下，仍旧使用1倍的方案
			dpr = 1;
		}
		scale = 1 / dpr;

		//
		var metaEl = "";
		metaEl = doc.createElement('meta');
		metaEl.setAttribute('name', 'viewport');
		metaEl.setAttribute('content', 'initial-scale=' + scale + ', maximum-scale=' + scale + ', minimum-scale=' + scale +
			', user-scalable=no');
		if (docEl.firstElementChild) {
			docEl.firstElementChild.appendChild(metaEl);
		} else {
			var wrap = doc.createElement('div');
			wrap.appendChild(metaEl);
			doc.write(wrap.innerHTML);
		}
	})();

})(document, window);
